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Element 62 - Samarium (Sm)
From the mineral smarskite, named after a Russian mine official, Colonel V.E. Samarsky; discovered 1879. Calcium chloride crystals treated with smarium have been employed in lasers--devices for produceing beams of light intense enough to burn metal or bounce off the moon.
Properties
Atomic Number
:
62
Atomic Weight
:
150.36
Electron Configuration
(at ground state):
1s
2
2s
2
2p
6
3s
2
3p
6
3d
10
4s
2
4p
6
4d
10
4f
6
5s
2
5p
6
6s
2
Oxidation States
(Bold most stable):
+3
, +2
Boiling Point
(K):
2067
Melting Point (K):
1347
Density
(at 300K -- g/cm
3
):
7.52
Atomic Volume (at 300K -- cm
3
/mol)
19.90
Number of stable
isotopes
:
6
Number of natural
radioactive
isotopes:
1
Mass Number
(Bold naturally occurring) --
Half-Life
--
Disintigration Type
:
146
-- 7 x 10
7
years --
alpha particle
emission
151
-- 93 years --
beta particle
(
electron
) emission
Covalent Radius (Å):
1.62
Atomic Radius (Å):
1.81
First
Ionization Potential
(V):
5.63
Electronegativity
(Pauling's):
1.17
Specific Heat
Capacity (at 300K -- J g
-1
K
-1
):
0.197
Heat of Vaporization (kJ/mol):
191.63
Heat of Fusion (kJ/mol):
11.09
Electrical Conductivity (at 293K for polycrystalline material -- 10
6
-1
cm
-1
):
1.1
Thermal Conductivity (at 300K -- W m
-1
K
-1
):
13.3
Crystal Structure:
Rhombohedral
Acid
-
Base
Properties:
Very basic